Bag sewing apparatus



Dec. 22, 1936. E, ZIMMERMANN 2,065,413

BAG SEWING APPARATUS Filed April 13, 1953 Patented Dec. 22, 1936 ATENT OFFICE BAG SEWING APPARATUS Ernst Zimmermann,

to Gummi-Tank A.- Glarus, Switzerland Kongen, Germany, assignor G., Rubber Tank Ltd.,

Application April 13, 1933, Serial No. 666,002 In Germany April 20, 1932 15 Claims.

My invention relates to improvements in bag sewing apparatus, and more particularly in apparatus. by means of which the opening of the bag is closed by chain stitches, and in which prior to sewing the upper rim of the bag is held by means of a clamping device provided with guiding means for the sewing apparatus. The object of the improvements is to provide an apparatus of this type in which the sewing apparatus is'securely supported, so that the bag may be readily and rapidly sewn. With this object in View my invention consists in providing the guiding means for the sewing apparatus with a frame which is adapted to be supported on the filled bag, and whichis equipped with stretching means for the opening of the bag.

For the purpose of explaining the invention several examples embodying the same have been shown in the accompanying drawing in which the same reference characters have been used in all the views to indicate corresponding parts. In said drawing,

Fig. 1 is an elevation showing the top part of the bag to be sewed and the sewing appara tus mounted thereon,

Fig. 2 is a'sectional elevation taken on the line 2-2' of Fig. 1,

Figs. 3 to 5 are detail views partly in section showing the needle in difierent positions,

Fig. 6 is a detail sectional elevation taken on the line 6-6 of Fig. 5.

My improved bag sewing apparatus comprises av frame adapted to be supported on the bag and the sewing apparatus movable thereon.

"In the construction shown in Figs. 1 to 6 the frame comprises two rails 3 which are angular in cross-section and two cross-members 4 connecting the rails at their ends, the said crossmembers. being curved upwardly from the rails. and being connected at their top ends by a rod 5. On the said rod a stretching device is mounted, by means of which the rim 2 of the bag I is stretched prior to sewing. As shown the stretching device comprises a hook 6' fixed to one end of the rod 5, and a hook I! which is shiftable' at the opposite end of the rod 5, and which is acted upon by a spring 9. The hook II is secured to-a block II] which is formed with a bore, and which is slidable on the rod 5. The block In is connected by a spring 9 with a block 1 adapted to be clamped to the rod 5 at any part of the length thereof by means of a screw 8. Prior to sewing the rim 2 of the bag is attached to the hook 6, and after stretching the same it is attached with its opposite end to the hook H,

whereupon it is stretched by the spring 9. The guide rails 3 of the frame are supported on the filled bag I, and they provide reliable guiding means for the sewing apparatus. The said sewing apparatus is supported on the rails 3 by 5 means of downwardly directed arms I3 carrying guide rollers It.

On the arms l3 the casing l2 of an electrometor is mounted which is adapted to drive the sewing apparatus through the intermediary of 10 a reducing gearing mounted in the bottom part of the casing I2.

At its top end the motor casing is provided with a handle I5 and a terminal I6 connected with a lead l1. At the side of the motor cas- 15 ing a second handle I8 is provided by means of which the sewing apparatus may be shifted by hand on the rails 3. By means of the reducing gearing provided in the bottom part of the motor casing rotary movement is imparted 20 to a driving disk 2|]. The said driving disk 2!] carries a downwardly directed eccentric bolt 2| which is connected by a link 22 with a coupling member 23 of a reciprocating needle bar 24. The needle bar 24 is guided in bearing blocks 21 and 28 secured to or made integral with two arms 25, 26 connected with the motor casing. To a bracket 29 secured to the needle bar 24 a hookshaped needle 30 is secured which is provided with a rockable tongue 36 (Fig. 3). 30

At the end projecting from the block 28 the needle bar 24 is tubular in form, and in its bore a thread brake is mounted. As shown the said brake comprises a cylindrical slide pin 44 mounted within the tubular end of the needle bar 24 and carrying laterally projecting pins guided in longitudinal slots of the said tubular end. The slide pin 44 is held between two coiled springs 46 and 41 bearing with their outer ends on the end walls of the bore of the tubular part of the needle bar 24. Through a transverse bore of the pin 44 the sewing thread is passed. By the springs 46 and 4'! acting on the slide pin 44 the tension of the thread is regulated While the needle bar 24 reciprocates. 45

The bearing 28 for the needle bar 24 carries two stitch plates 37 and 38 spaced from each other to provide room for the rod 5 of the frame and the rim 2 of the bag. On the stitch plate 31 a controlling slide latch opener 34 is shiftable, which is guided by means of a rod 33 in a bore of the bearing block 28, and which is adapted to be operated through the intermediary of a slide 32 carrying guide rollers from a controlling cam 3| provided circumferentially of the driving disk 20. The controlling slide 34 is formed with a cut-out portion 35 which is adapted to rock the tongue 36 of the needle 33 rearwardly and on the stem of the needle at the beginning of the stitching movement.

The motor casing is provided with two arms 40 on which a thread bobbin 39 and a tensioning and releasing device 42 for the said bobbin are mounted. The thread is guided to the threadbrake and the needle through eyes 43 and a thread-guiding opening made in the stitch plate 38.

The free end of the thread is held by means of a clamping device shown in detail in Fig. 6 and comprising a shoulder 50 and a clamping plate formed with a guide pin 52 and acted upon by a spring 53.

The thread taken from the bobbin 39 is passed through the thread eye 43, the bore of the slide pin 44 and the opening made in the stitch plate 38, whereupon its end is clamped between the shoulder 50 and the clamping plate 5|.

The chain stitches for sewing the bag are made as follows:

The needle 30 is passed through the rim 2 of the bag after its tongue 36 has been rocked rearwardly by the upward movement of the slide 34 in the manner shown in Fig. 3. After being passed through the bag the needle catches the thread located before the stitch hole, as is shown in Fig. 4, and it pulls the same through the rim 2 of the bag and into the position shown in Fig. 5 while forming the thread into a loop, the tongue 36 being placed by the fabric of the bag on the eye of the needle so as to prevent the loop from leaving the needle 30. The sewing apparatus is shifted in the direction of the seam being made, and thereby the loop which has been pulled through the fabric is placed in the same direction and on the rim of the bag. When the needle 30 is againmoved forwardly and towards the rim 2 of the bag the slide 34 rocks the tongue 36 rearwardly, so that the needle 30 is free to pass within the loop through the rim 2 of the bag and to produce a second loop from the thread located in front of the stitch hole 49, the said second loop being passed through the first loop lying on the rim of the bag. Thereafter the stitching operation is repeated.

I claim:

1. A bag sewing apparatus, comprising a frame having a pair of rails adapted to be supported on the top of the filled bag and means located in position, when the frame is placed on the filled bag, for holding the open end of the bag tensioned to bring the sides of the rim together, and a bag sewing apparatus movable on said frame, said sewing apparatus comprising a hook-shaped needle carrying a rockable tongue, a controlling member adapted to be moved into and out of position for acting on said tongue, a motor, a cam disk connected with said motor and adapted to operate said controlling member and crank mechanism connected with said cam for imparting reciprocating movement to said needle.

2. A bag sewing apparatus, comprising a frame having a pair of rails adapted to be supported on the top of the filled bag and means located in position, when the frame is placed on the filled bag, for holding the open end of the bag under tension with the sides of the rim parallel and close together, and a bag sewing apparatus movable on said frame, said sewing apparatus comprising a hook-shaped needle, a reciprocating rod adapted to operate said needle, a motor for operating said rod, means for supplying thread to the needle, and a resiliently-acting take-up on said rod.

3. In a bag-closing apparatus, a frame comprising a pair of rails rigidly secured together in spaced-apart relation so that they can be supported on the shoulders of a filled bag with the neck of the bag extending up between them, and means at the ends of the frame for engaging the neck of the sack and tensioning it to bring the opposed sides into contiguous parallel relation whereby they can be conveniently secured together.

4. A device as in claim 3, wherein said engaging means acts resiliently to hold the neck of the bag under tension.

5. A device as in claim 3, the end portions of the frame being arched and said engaging means being located near the top of the respective arches at a substantial height above said rails.

6. In a bag-closing apparatus, a frame comprising a pair of rails rigidly secured together in spaced-apart relation so that they can be supported on the shoulders of a filled bag with the neck of the bag extending up between them, means at the ends of the frame for engaging the neck of the bag and tensioning it to bring the opposed sides into contiguous parallel relation whereby they can be conveniently secured together, and a sewing machine supported on said rails and movable lengthwise thereof.

'7. A device as in claim 6, the sewing machine having legs resting on said rails and holding the machine at a substantial distance above the shoulders of the bag.

8. A device as in claim 6, wherein the sewing machine is moved by hand along the rails, said device including an electric motor for driving the sewing machine.

9. A bag-sewing apparatus comprising a sewing machine, means for supporting the sewing machine in operative relation to'the closed neck of a filled bag, a horizontal pivoted latch needle, means for operating the needle to sew the neck of the bag, means for opening the latch of the needle, and means for operating the latch opening means in timed relation with the needle movements so as to open the latch of the needle while the same is withdrawn from the material of the bag.

10. A bag-sewing apparatus comprising a sewing machine, means for supporting the sewing machine in operative relation to the closed neck of a filled bag, a horizontal latch needle, means for operating the needle to sew the neck of the bag, means for opening the latch of the needle, said means comprising a member having an opening to receive the end of the latch, and means for moving said member into operating position at the beginning of a forward stroke of the needle.

11. A bag sewing apparatus comprising a sewing machine, a track supporting the machine for movement parallel to the rim of the bag to be closed by the action of the machine, a horizontal needle having a pivoted latch, means for operating the needle to sew up the mouth of the bag, means for opening the pivoted latch of the needle, said latch opening means being movable with reference to the needle, and means for moving said latch opening means in timed relation with the movements of the needle.

12. A bag sewing apparatus comprising a sewing machine, a track supporting the machine for movement parallel to the rim of the bag to be closed, a horizontal needle having a pivoted latch, means for operating the needle to sew up the mouth of the bag, means for opening the pivoted latch of the needle, said latch opening means comprising a movable member with an orifice to receive the end of the latch, and means to move said member into position to engage the latch before the latch reaches the cloth of the bag and then moving said member out of the way of the latch.

13. In a bag sewing apparatus, means for supporting material to be sewed, a sewing needle having a pivoted latch, means for operating the needle, latch opening means, said latchopening means comprising a movable element, and means for moving it into and out of the path of the latch in timed relation to the needle movements.

14. A bag sewing apparatus comprising rails adapted to be supported by the shoulders of a filled bag, cross members connecting said rails, means for stretching the mouth of the bag during the sewing operation, a mechanism movable on said rails including sewing means, a motor for driving the sewing means, and connections from the motor to the sewing means.

15. A device as in claim 14, said mechanism being movable only manually along the rails.

ERNST ZIMMERMANN. 

